Railway signaling.



,. -J. B. STRUBLE RAILWAY SIGNALING. APPLICATION FILED J LY 25,1 13.

Patented Apr. 7, 1914 QQ I a T N 0 g E h.

WITNESSES UNITED STATES PATENT ora ion.

d'ACOB B. STRUIBLE, OF SAN FRANCISCO,

CALIFORNIA, ASSIGNOR TO THE' UNION SWITCH AND SIGNAL COMPANY, OFSWISSVALE, PENNSYLVANIA, A CORPORA- 'IION OF PENNSYLVANIA.

Specification of Letters Patent.

Patented Apr. 7, 1914.

I Original application filed March 4,1904, Serial No. 196,474. Dividedand this application filed July 25,

1913. Serial No.781,084.

To all whom, it may concern:

I Be it known that I, JAooB B. STRUBLE, a citizen of the United States,residing at San Francisco, county of San Francisco, and State ofCalifornia, formerly residing in the borough of Manhattan, city, county,and

electric railways wherein one or both of;

the track rails are used as a return conductor for the propulsioncurrent.

It is customary in electric railways to employ direct current foroperating the car on train motors and to employ one'or both of the railsas a return conductor for the propulsion current.

In the present invention I employ alternating current in the trackcircuits of the signaling system, to which translating mechanismsincluded in the track circuits, are

. responsive in their control of the railway signals.

I will describe a railway signaling system embodying my invention andthen point out the novel features thereof in claims.

In the accompanying drawings, Figure l is a diagrammatic viewillustrating a portion of an electric railway having a signaling systemembodying my invention applied thereto. Fig. 2 is a detail View of animpedance-in the form of a reactance or choke coil, which may beemployed in my invention.

Similar letters of reference designate corresponding parts in the twoviews.

Referring now to the drawings and particularly to Fig. 1, in thepractice of my invention one of the lines of rails of the railway isdivided into a series of sections 1, 2, 3, etc., by means of insulationat suitable points, while the other line of rails 4 is preferably madeelectrically continuous. The sections 1, 2, 8, etc., maygfhe' of anydesired length and in the art each section and the opposite portion ofthe continuous rail 4 is generally termed a block section.

6 designates a direct current generator bonded or joined together forthis purpose in the manner hereinafter described.- e

14 designates a railway signal, at least one return for the direct orpropulsioncurrent is lathrough one or both track rails, they being beingprovided at the beginning of each block section. The railway signals 14may be of any desired construction and they each preferably comprise asemaphore and mechanism or means for movlng the sefna- PhOl from oneposition of indication to another.

5 designates an alternating current,..gen.. erator. One pole of thealternatingcur'rent generator is here shown as being connected "with theline of rails 4, while the other pole of the, generator 5 is connectedwith a con ductor 5 extending along the line of railway, and which, atsome suitable point, for v example, at the end of the railway, iselectrically joined to the line of rails 4.

6 designates transformers, at .least one transformer being provided foreach block section.

As shown in the drawings, the primary windings of the transformers arein series with the conductor 5*, and their secondary windings areelectrically connected to the opposite lines of rails comprised in eachblock section. It will be understood that other arrangements of theconductors extending from the alternating current generator 5 maybeprovided as well as other arrangements of the primary windings of thetransformer. The employment of transformers permits of a high tensioncurrent in the transmission conductor 5 and the use of low tensioncurrents in the track circuits.

To prevent an excessive amount of'alternating current flowing in a trackcircuit transformer ("i-may be built with such resistance as is wellknown. in the art. The

prises all OILJPOIiZlOl'lS of the track rails of track circuit of eachblock ,section com-2'" the'block section, a transformer or the secondarywinding thereof, and a translating mechanism or device. I

8 designates translating mechanisms or devices, one being provided foreach track circuit. Each translating mechanism is in the form of arelay, the coil or coils 18 of which are included in the track circuit.The armature 19 of the relay is pivotally mounted in operativerelation-to the .poles of the magnet core energized by the coil or coils18. The form of translating device andits operation is more particularlyset forth in my Patent No. 819,823, issued May 1, 1906. This form oftranslating mechanism as set forth in the patent hereinbefore referredtois responsive to the alternating current in the track circuit for oneof its operations to control a local circuit 13, which circuit includesa source of' electrical energy, and a controlling device of themechanism of the signal 14, and when the alternatin-g current-is shuntedfrom the coil or coils 18, for example, by the wheels and axles of thetrain on the track rails of the track circuit in which the translatingmechanism is included, it will respond to again control the circuit 13.In other words, when alternating current is flowing through the coil orcoils 18, the armature 19 will move to close the circuit 13 and whenalternating current is shunted from the coil or coils 18, the armature19 will move to open the circuit 13. In both conditions of the circuitthe mechanism of the railway signal will be affected to have thesemaphore thereof give difi'erent indications. Any other form oftranslating mechanism may be employed.

17 designates impedances in the form of reactance or choke coils (seeFig. 2), which may be constructed in accordance with the rules wellknown in the art. [The coils may be employed to connect adjacent ends ofthe insulated track sections,"and they may also be connected across thewires or conductors connecting the translating mechanisms with the trackrails. These coils will permit of direct current flowing through thembut will oppose 'the flow of alternating current through them, theeffect, therefore, being to confine alternating current to the severaltrack circuits and to permit direct current to pass from the trackrailsof one track circuit to the track rails of another track circuit. Inother words, the direct or propulsion current for the car motors may beflowing through both track rails as a return without in any wayaffecting the apparatus connected therewith.- Each coil is made with lowohmic resistance so as to form an easy path for direct current from railto rail, while the flow of alternating current is opposed by thereactive effect of self-induction so that the reactance coil has achoking effect onthealternating current but not on I claim is:

the direct current. The coils and the other I instruments connected withthe track circuits will be constructed in the proper proportions'andwith the proper resistances to carry outmy inventiom Having thusdescribed my invention, what 1. In combination with a railway having.one rail electrically continuous and the other divided by insulationinto track sections,'of a direct current generator having one poleconnected with the track rails, reactance coils connecting adjacent endsof-the' insulated sections, react-ance coils connecting the. sectionswith the continuous rail, and a signaling system said system comprisingtrack circuits, an alternating current supply for each track circuit anda translating mecha-' nism for each track circuit which is operated fromthe alternating current in the track circuit. c

2. In anelectric railway signaling system employing a closed signalcontrolling one rail being divided into insulated sec-- tionscorresponding to the block sections a signal for each block sectionoperable y an alternating current, a source of alternating current forsaid signals, a source of direct current for propelling the railwaycars, means for permittingthe direct cur-' rent to pass from oneinsulated rail sectionto another and for preventing alternatingcurrent'from passing from one insulated rail section to another, and aninductive bond connecting the rails comprisedin each block section.

3. In a system of electrical distribution and signaling for railways,the combinationof two sources of electrical energy delivering currentsdiffering in character, outgoing feeder conductors, two track rails, onecontinuous and the other divided into sections track circuit, aplurality of block sections,

to form blocks, a reactance device interposed between each two adjacentsections, and a reactance device connected across the rails of eachblock.

4:. In combination, a railway the trackway of which is divided to formtrack sections, a direct current generator having one terminal connectedwith the track rails, rcactance coils connecting adjacent ends of thesections, reactance coils connecting the opposite rails of the sections,and a signaling system comprising track circuits forthe sections, a'source of alternating signaling current for each track circuit, and atranslating mechanism for each track ,clrcuit which is controlled by thealternating signaling current in the track circuit.

5. In combination, an electric railway both track rails of which areincluded in the circuit for the propulsion current, a source ofpropulsion current of one charaeter,.a plurality of block sectionsformed bywinsulations in one of the lines of track rails; a source ofsignaling current connected with the rails of each section and difieringin character from the propulsion current, a translating device connectedwith the track rails of each section, signals controlled by saidtranslating devices, means for permitting the propulsion current to passfrom each insulated track section to the adjacent track sections and forpreventing the passage of the signaling current, and means forpermitting the propulsion current to pass from the insulated railsection of each block section to the other rail and for preventing thepassage of the signaling current.

6. In combination, an electric railway both track rails of which areincluded in the circuit for the propulsion current, a source of directpropulsion current, a plurality of block sections formed by insulationsin one 20 of the lines of track rails, a source of alternating signalingcurrent connected with the rails of each section, a translating deviceconnected with the rails of each section and responsive to the signalingcurrent but not to the propulsion current, signals controlled by saidtranslating devices, reactances con: necting the insulated track rail ofeach block section with the insulated track rail of each adjacent blocksection, and a reactance for each block section connecting the insulatedtrack rail with the opposite rail.

In testimony whereof I afiix my signature in presence of two witnesses.

' JACOB B. STRUBLE.

Witnesses! HENRY B. LESTER,

J OHN B. MARTIN.

